1. Technical Field
The present invention relates to communications methods and apparatus, and particularly, but not exclusively, to methods of operating mobile communications networks, and to mobile telephones for use with mobile communications networks.
2. Related Art
European Patent Application No. EP 0782359 A2 discloses a mobile terminal having a user-activated pager mode. When the user has selected pager mode, the mobile terminal sends a registration message with a power down indication to de-register itself on the cellular network, and displays “Pager Mode Activated” to indicate that incoming telephone calls will not be responded to. If a call is made to the mobile terminal while it is de-registered, i.e. inactive, the network does not send the call to the mobile terminal but forwards the call to a voice mail service, which sends a voice mail waiting message or a callback number message to the mobile terminal. Since the mobile terminal is currently inactive, the network will not route such messages to the mobile terminal but will wait until such time as the mobile terminal periodically re-registers itself with the network so as to receive any queued SMS or other types of messages from the network.
U.S. Pat. No. 5,828,949 discloses a mobile phone/pager comprising a mobile phone portion and a pager portion. The user can switch the mobile phone portion off, and when he does so the network responds by recording the mobile phone portion as de-registered (inactive). If a call is made while the mobile phone portion is switched off, the network first notes that the mobile phone portion is switched off, and then proceeds to check whether the called mobile phone is recorded as having dual pager/mobile telephone capability, and if so sends a page request to a paging network to page the pager portion. The network may announce to the caller a potential delay in call delivery. Upon receipt of the paging signal, the pager portion activates the mobile phone portion, which sends a registration signal to the network. Upon receipt of the registration signal, the network then routes the incoming call to the mobile phone portion in the normal manner. The mobile phone portion switches itself off when the call is ended.
U.S. Pat. No. 5,818,920 is concerned with preventing calls in a telecommunications network from being connected during specified periods of time, such as when calls to the desired communication terminal have been forwarded to a new communication terminal in a new time zone and the subscriber at the calling communication terminal in unaware of the local time of the new communication terminal. One form of prevention device is disclosed which informs the calling communication terminal of the local time of the new communication terminal prior to connection and requests the calling communication terminal to confirm whether the connection should be made. Another form of the prevention device is disclosed which automatically prevents the connection from being made and informs the calling communication terminal that the connection will not be made.